The aggregation of capital over vintages in a model of embodied technical progress

The paper considers how to measure capital in a model where technical progress is embodied in new units of capital. This embodiment model also assumes that once new units of capital are installed, it cannot be “unbolted” and sold on the second hand market. A significant difference between this Solow–Harper model and the traditional capital services model due to Jorgenson and his coworkers is that rising real wage rates will generally induce early retirement of assets; i.e., this model can provide an explanation for obsolescence. The paper studies how to aggregate over vintages and how to measure depreciation in the context of this embodiment model. These problems are more complicated than the corresponding problems in the traditional capital services model because the age of retirement of an asset is endogenous in the embodiment model. The paper uses duality theory to simplify the exposition.

基于改进遗传算法的沥青路面再生工厂布局优化

为了帮助沥青路面再生工厂获得更好的经济与环境效益,提出一种基于改进遗传算法的布局优化方法。首先,确定再生工厂布局的约束条件,并以非物流相关性最大、物料搬运成本最低和碳排放最少作为优化目标建立工厂布局优化模型;其次,基于初始布局方案,采用实数分层编码及排列组合方法对各功能区的初始位置进行交叉互换,并根据约束条件进行筛选,得到合适的初始种群;再次,针对横坐标层与纵坐标层进行算数交叉,变异时坐标层采用多点变异,放置方式层采用单点变异,并引入模拟退火算子;最后,以某再生工厂为例对改进算法进行验证。结果表明：改进后的遗传算法迭代次数较传统遗传算法减少34次,目标函数值较文献中遗传算法减小0.009 9,提高了算法的寻优能力;优化后的方案每日物料搬运成本减少14 468.85元,碳排放减少30.59 kg,验证了方法的有效性。研究中所提出的优化方法效率较高,可为沥青路面再生工厂的建设提供技术支持。     

《无锡商业职业技术学院学报》载文统计分析

用文献计量学、数理统计的方法,对2007--2011年无锡商业职业技术学院学报所载1020篇论文进行统计分析．结果表明：学报已经形成平均每年有19个省市自治区的91个机构作者的投稿网络与研究体系;学报载文量适当;基金论文比逐年提高、出版时滞逐年降低;论文主题分布符合学报主办单位性质;外省市稿源有巨大的挖掘潜力;核心作者群处于形成阶段,高产作者群尚未形成。     

Ruin probabilities in models with a Markov chain dependence structure

In this paper we derive explicit expressions for the probability of ruin in a renewal risk model with dependence among the increments (Z _k ) _k>0. We study the case where the dependence structure among (Z _k ) _k>0 is driven by a Markov chain with a transition kernel that can be described via ordinary differential equations with constant coefficients.     

A cost-benefit analysis of the random assignment UK Employment Retention and Advancement Demonstration

This article presents a cost-benefit analysis of Britain’s Employment Retention and Advancement (ERA) demonstration, which was evaluated through the first large-scale randomized control trial in the UK. ERA used a combination of job coaching and financial incentives in attempting to help long-term unemployed men and low-income lone parents sustain employment and progress in work once they were employed. Using both administrative and survey data, ERA’s effects on benefits and costs were estimated through impact analyses, which exploited the experimental design. The findings indicated that ERA was cost beneficial for long-term unemployed adult men, but not for lone parents. The key findings appear robust to sensitivity tests. Uncertainty, as implied by the SEs of the estimated impacts, was addressed through a Monte Carlo analysis, an approach seldom previously used in cost-benefit analyses of social programs.     

Is There Long Memory in Indian Stock Market Returns? An Empirical Search

The issue of long memory, though has important theoretical and practical implications, has not received much attention in India. This article examines the issue of long memory in mean of the stock returns by employing a set of sophisticated time-series tests including a bias reduced log periodogram test of Andrews and Guggenberger. The study used daily values of 29 major indices including sectoral indices traded on the National Stock Exchange and Bombay Stock Exchange from April 2003 to March 2012, which provide insights into relation between composition of indices and long memory. The findings of the study suggest significant presence of long memory in mean returns of the medium- and small-sized indices and weaker evidences for large cap indices. Further, the study identifies a relationship between presence of long memory and market structure variables. The use of linear models in the presence of long memory would result in incorrect inferences, and this calls for investigation of appropriate long memory model to generate profits in Indian stock market.     

飞行器目标监控系统抗干扰技术研究

飞行器目标监控系统是飞行器实现可靠飞行的重要技术保障。研究了飞行器目标监控 系统的工作机理,分析了监控系统抗干扰性能,提出了具有高抗干扰容限的伪码组合扩频技 术。仿真实验结果表明,采用伪码组合扩频技术可提高通信系统的抗干扰能力。     

北京城市女性独生子女生育意愿和生育行为研究

利用北京市人口研究所两次独生子女问卷调查所获第一手资料,对北京城市女性独生子女婚育群体进行考察。在生育意愿方面,女性调查对象的意愿生育水平呈现偏低发展走向,但二孩生育意愿出现明显上升,不过对于生育"政策二孩"的选择呈现明显的矛盾心理和不确定性;在实际婚育状况方面,初婚初育时间在后移,婚后离开父母单独居住开始增多,孩子以双方父母照料为主。政府应积极鼓励双独夫妻生育两个孩子,发挥"政策二孩"生育对于缓解人口结构快速老化的功能。     

Optimum allocation in multivariate stratified random sampling: stochastic matrix mathematical programming

The allocation problem for multivariate stratified random sampling as a problem of stochastic matrix integer mathematical programming is considered, minimizing the estimated covariance matrix of estimated means subject to fixed cost or fixed total sample size. With these aims the asymptotic normality of sample covariance matrices for each strata is established. Some alternative approaches are suggested for its solution. An example is solved by applying the proposed techniques.